Leo Sher, M.D.

A research report, “Sleep regularity is a stronger predictor of mortality risk than sleep duration: A prospective cohort study” has been published in Sleep online ahead of print (1). This prospective cohort study has found that regular sleep patterns are more important to health and longevity than spending eight hours in bed.

Researchers compared how sleep regularity and duration predicted risk for all-cause and cause-specific mortality. They calculated Sleep Regularity Index (SRI) scores from >10 million hours of accelerometer data in 60,977 UK Biobank participants (62.8±7.8 years, 55.0% female, median [IQR] SRI: 81.0 [73.8-86.3]). Mortality was reported up to 7.8 years after accelerometer recording in 1,859 participants (4.84 deaths per 1000 person-years, mean (±SD) follow up of 6.30±0.83 years). Higher sleep regularity was associated with a 20-48% lower risk of all-cause mortality, a 16-39% lower risk of cancer mortality, and a 22-57% lower risk of cardiometabolic mortality, across the top four SRI quintiles compared to the least regular quintile. Results were adjusted for age, sex, ethnicity, and sociodemographic, lifestyle, and health factors. Sleep regularity was a stronger predictor of all-cause mortality than sleep duration, by comparing equivalent mortality models, and by comparing nested SRI-mortality models with and without sleep duration.

Higher risk of mortality by cardiometabolic causes was associated with both irregular sleep and short sleep duration in this study. Previously, multiple experimental and epidemiological evidence linked sleep regularity and duration with cardiometabolic health.

The results of this study confirm an important role for sleep duration in predicting mortality but reveal that sleep regularity is an even stronger predictor. The authors suggest that sleep regularity may be a simple, effective target for improving general health and survival.

References

1. Windred DP, Burns AC, Lane JM, Saxena R, Rutter MK, Cain SW, Phillips AJK. Sleep regularity is a stronger predictor of mortality risk than sleep duration: A prospective cohort study. Sleep. 2023 Sep 21:zsad253. doi: 10.1093/sleep/zsad253. Epub ahead of print.